The Right Oven Temperature For Perfect Prime Rib, Every Time
Cooking prime rib isn't necessarily hard, but it does take technique and proper cooking methods for restaurants to achieve prime rib perfection. Texas Roadhouse, for example, marinates its prime rib for up to 24 hours, though you can go the simple route and let it sit out with some seasonings for an hour. You can certainly make prime rib at home; while the preparation can vary, for the best prime rib results, keep the temperature in the low range, meaning somewhere between 300 and 325 degrees Fahrenheit.
Prime rib isn't supposed to be overcooked. Most prime rib is cooked rare to medium-rare, though you could go as high as medium if your guests prefer it that way. That said, cooking it at a low temperature is important to ensure it doesn't edge into that overcooked territory. Some recipes and cooking methods might tell you to sear the prime rib first, or to cook it at a very high temperature for a short time to get a good crisp on the exterior. This is fine, but the majority of cooking should be done within a lower temperature range.
How to tell when your prime rib is done
Once you cook that perfect grocery store prime rib, the most accurate way to determine whether your prime rib is done is to check its temperature. Using a meat thermometer, remove the prime rib from the oven once its internal temperature hits 125 degrees Fahrenheit. That temperature creeps up to just past 130 degrees for medium-rare. If you want the prime rib cooked a little more, taking it out at 130 degrees Fahrenheit cooks it to medium as it rests. The actual amount of cooking time depends on the size of the prime rib and your desired temperature, but it's often somewhere in the ballpark of around an hour.
A nicely cooked prime rib should be pink in the center and cooked to gray or brown around the edges. The exterior should also be slightly caramelized, but, when you cut into the prime rib, the pink color should extend all the way out to just past the edges. Any further in, and some would say it's overcooked.